One of the fastest growing areas of communications technology is related to automobile network solutions. Many existing automobiles have had telematics devices installed, and many new cars are now being provided with at least some level of telematics service when sold. Commensurate with the increasing number and variety of these services, demands on telematics service call centers have also grown.
Telematics services include, but are not limited to, turn-by-turn directions and other navigation-related services provided in conjunction with GPS based chipsets and components, and airbag deployment notification and other emergency or roadside assistance-related services provided in connection with various crash and collision sensor interface modules and sensors located throughout the vehicle. Telematics services also include “infotainment-related” services wherein music, Web pages, movies, television programs, video games and/or other content are downloaded by an “infotainment center” operatively connected to the telematics unit. For example, music content may be downloaded for current or later playback. In addition, a telematics unit may provide vehicle location and heading information to a subscriber.
One of the most important aspects of telematics services is the ability to guide a user based on their current position. This service relies, however, on the ability to accurately determine a vehicle's or telematics unit's current position. Typically, as noted above, this is accomplished via known GPS technologies. However, in instances where GPS signals are unavailable or unreliable, the unit may use “dead reckoning” to navigate based on vehicle data collected while the vehicle was at a reliably known position, e.g., a last good GPS location.